Oligosaccharide-camptothecin conjugates as potential antineoplastic drugs: Design, synthesis and biological evaluation.

Thirty novel 20 (S)-O-linked camptothecin (CPT) glycoconjugates were synthesized. They showed more potent in vitro cytotoxicities over irinotecan, but very weak direct topoisomerase I (Topo I) inhibition was observed at 100.0 µM. Oligosaccharide types, length of a PEG linker and acetyl groups exerted obvious effects on cytotoxicity, selectivity, water solubility and stability of the newly synthesized CPT glycoconjugates. Construct 40, with a bleomycin (BLM) disaccharide linked to diethylene glycol in the introduced ester moiety, demonstrated a superior antitumor activity and a distinct selectivity compared to CPT. No toxicity was detectable in animal acute toxicity intravenously (160 mg/kg). Collectively, attachment of oligosaccharides with tumor targeting to 20 (S)-OH of CPT could offer a solution to the daunting problems posed by current Topo I poisons.

Antitumor activity and structure-activity relationship of heparanase inhibitors: Recent advances.

Heparanase (HPSE)-directed tumor progression plays a crucial role in mediating tumor-host crosstalk and priming the tumor microenvironment, leading to tumor growth, metastasis and chemo-resistance. HPSE-mediated breakdown of structural heparan sulfate (HS) networks in the extracellular matrix (ECM) and basement membranes (BM) directly facilitates tumor growth and metastasis. Lysosome HPSE also induces multi-drug resistance via enhanced autophagy. Therefore, HPSE inhibitors development has become an attractive topic to block tumor growth and metastasis or eliminate drug resistance. In this review, we summarize HPSE inhibitors applied experimentally and clinically according to interaction with the binding sites of HPSE and participation of growth factors. The antitumor activity and structure-activity relationship (SAR) are also emphasized.